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palindrome

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Join Date: Nov 2009

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Reputation: kisan is an unknown quantity at this point

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kisan

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palindrome

-1

Nov 2nd, 2009

how to check if the string is pallindrome or not in python??

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Join Date: Nov 2007

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Reputation: mn_kthompson is an unknown quantity at this point

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mn_kthompson mn_kthompson is offline

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Nov 2nd, 2009

There is no built in function that I know of to check that.

On thing you might try doing is reversing the string and then comparing each element.

 Help with Code Tags 
 python Syntax (Toggle Plain Text) 
inString = 'racecar'
reversestring = ''
for i in range(0,len(inString)-1:
   reversestring.append(inString[i]
inString = 'racecar'
reversestring = ''
for i in range(0,len(inString)-1:
   reversestring.append(inString[i]

Another way to do it would be to compare the first element to the last element in your string and make sure they match the whole time. One thing that is helpful to remember when doing this is that string[-1] will give you the last element of the string, and string[-2] will give you the second to last. So if your string is racecar then inString[0] should equal inString[-1] and inString[1] should equal inString[-2] etc.

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Join Date: Jul 2009

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Reputation: masterofpuppets is an unknown quantity at this point

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masterofpuppets masterofpuppets is offline

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Nov 2nd, 2009

there are a couple of posts regarding palindromes in the forum, have a look around.... but basically the algorithm is what mn_kthompson suggested

My site ->> http://8masterofpuppets8.webs.com/
"My belief is stronger than your doubt."

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Join Date: Nov 2009

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Reputation: kisan is an unknown quantity at this point

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kisan

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Nov 3rd, 2009

Thank you very much!!
It was helpful. But how could we test if the given string is pallindrome or not. I need a syntax that returns true if the string is pallindrome otherwise false.

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Reputation: abhi_elementx is an unknown quantity at this point

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abhi_elementx abhi_elementx is offline

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Nov 3rd, 2009

just compare the inString with reversestring using the == operator

Last edited by abhi_elementx; Nov 3rd, 2009 at 6:04 am.

PEACE !

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Reputation: snippsat is an unknown quantity at this point

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snippsat

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Nov 3rd, 2009

•

But how could we test if the given string is pallindrome or not. I need a syntax that returns true if the string is pallindrome otherwise false.

 Help with Code Tags 
 Python Syntax (Toggle Plain Text) 
>>> def is_palindrome(s): 
...     return s.lower() == s[::-1].lower()
... 
>>> is_palindrome('test')
False
>>> is_palindrome('racecar')
True
>>> is_palindrome('RACECAR')
True
>>> def is_palindrome(s): 
...     return s.lower() == s[::-1].lower()
... 
>>> is_palindrome('test')
False
>>> is_palindrome('racecar')
True
>>> is_palindrome('RACECAR')
True

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Reputation: abhi_elementx is an unknown quantity at this point

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abhi_elementx abhi_elementx is offline

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Nov 3rd, 2009

bravo!!! snipsat.
Dint know something like this exists in Python.

PEACE !

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Reputation: masterofpuppets is an unknown quantity at this point

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masterofpuppets masterofpuppets is offline

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Posting Whiz in Training

Nov 3rd, 2009

or you could do it using a loop:

 Help with Code Tags 
 Python Syntax (Toggle Plain Text) 
def isPalindrome( s ):
    s = s.lower()
    for i in range( len ( s ) / 2 ):
        if s[ i ] != s[ -1 -i ]:
            return False
    return True
 
>>> isPalindrome( "RACECAr" )
True
>>> isPalindrome( "test" )
False
>>> isPalindrome( "civiC" )
True
>>> isPalindrome( "ciniC" )
True
>>> isPalindrome( "cinac" )
False
>>>
def isPalindrome( s ):
    s = s.lower()
    for i in range( len ( s ) / 2 ):
        if s[ i ] != s[ -1 -i ]:
            return False
    return True

>>> isPalindrome( "RACECAr" )
True
>>> isPalindrome( "test" )
False
>>> isPalindrome( "civiC" )
True
>>> isPalindrome( "ciniC" )
True
>>> isPalindrome( "cinac" )
False
>>>

Last edited by masterofpuppets; Nov 3rd, 2009 at 8:49 am.

My site ->> http://8masterofpuppets8.webs.com/
"My belief is stronger than your doubt."

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Reputation: vegaseat is just really nice

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vegaseat

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DaniWeb's Hypocrite

Nov 3rd, 2009

Let's hope this is not homework and the OP had a chance to learn something.

In a true palindrome test you also need to remove everything but the case adjusted letters.
"Madam in Eden I'm Adam" is a palindrome.

May 'the Google' be with you!

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Join Date: Nov 2009

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Reputation: kisan is an unknown quantity at this point

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kisan

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Newbie Poster

python more

#10

Nov 4th, 2009

IT was quite helpful. so in case of palindromes how can we remove the symbols and capital letters using .upper and replace function?? for example
"Madam, in Eden I'm Adam!"